They are a shallow-water fish found at depths of up to 50 metres. In New Zealand, they are most abundant in harbours, estuaries, and muddy bays, particularly in the north.

Flatfish were introduced to the QMS in 1986 as a group, rather than individual species (species-specific catch reporting is now encouraged). The annual catch limit for flatfish has varied from 5,409 to 6,670 tonnes since 1986. Stock abundance of flatfish can vary markedly in response to environmental variation. Accordingly, catch limits may be changed frequently to respond to these fluctuations.

Yellowbelly flounder are caught year-round in the Firth of Thames and in Kaipara and Manukau harbours, most commonly in set nets.

Flatfish have delicate moist, flesh and benefit from light cooking. Brill and turbot, being larger fish, have denser flesh. Flatfish can be interchanged for one another in most recipes. Bake, grill, barbecue or fry. The flesh will flake easily when cooked.

'Right-eyed' flounders have an eye on each side of their head when they're larvae. As they grow their left eye shifts to the right side of their head and the body's left side becomes their flat underside. 'Left-eyed' flounders go vice versa.

Yellowbelly flounder is a good source of Vitamin B12 and Phosphorus; and a source of Iodine, Magnesium, Potassium, Selenium and Niacin (vitamin B3).

Seafood is a highly nutritious food and is a great source of protein. Many species are low in saturated fat and a number of them are a good source of Omega 3.